In a wireless communication system, a radio access network (RAN) may radiate on multiple carrier frequencies to define multiple wireless coverage areas. Each carrier frequency may define a wireless coverage area, or multiple carrier frequencies may, in combination, define a wireless coverage area. The RAN may assign wireless communication devices (WCDs) to one of the wireless coverage areas so that these WCDs can communicate (e.g., access the Internet or other networks) via the wireless communication system. More than one WCD may use each wireless coverage area. Furthermore, since each wireless coverage area may use a different carrier frequency, different WCDs may be able to simultaneously communicate via different wireless coverage areas without interfering with one another.
The multiple wireless coverage areas may physically or geographically overlap to some extent. Thus, when the RAN assigns a WCD to a carrier frequency so that the WCD can communicate, the RAN may have two or more candidate carrier frequencies to choose from. Current carrier frequency assignment techniques may attempt to balance the total number of WCDs per carrier frequency. However, such a simple carrier frequency assignment technique can result in the load on across all available carrier frequencies in a given physical or geographical region being unbalanced. In other words, the actual load on some carrier frequencies may be much higher than the actual load on other carrier frequencies, even if the total number of WCDs on each carrier frequency is roughly the same.
An unbalanced load across the carrier frequencies of a RAN can have a deleterious impact on the performance of the RAN, as some WCDs may be unable to acquire a reasonable amount of communication capacity. This, in turn, may result in the users of these WCDs becoming frustrated with their service. Ultimately, this frustration may impact the revenue of a wireless network operator that provides service via the RAN.